[Sync] Rename syncable_prefs to sync_preferences.

chrome/browser/profiles/profile_impl.h

Index: chrome/browser/profiles/profile_impl.h
diff --git a/chrome/browser/profiles/profile_impl.h b/chrome/browser/profiles/profile_impl.h
index 263c49956c49f4ba4cad047370baeda93c4c56af..b5d7c78318f00ebf4a616f0fc80455b43d50869d 100644
--- a/chrome/browser/profiles/profile_impl.h
+++ b/chrome/browser/profiles/profile_impl.h
@@ -58,7 +58,7 @@ namespace ssl_config {
 class SSLConfigServiceManager;
 }
 
-namespace syncable_prefs {
+namespace sync_preferences {
 class PrefServiceSyncable;
 }
 
@@ -222,8 +222,8 @@ class ProfileImpl : public Profile {
   // |io_data_| and others store pointers to |prefs_| and shall be destructed
   // first.
   scoped_refptr<user_prefs::PrefRegistrySyncable> pref_registry_;
-  std::unique_ptr<syncable_prefs::PrefServiceSyncable> prefs_;
-  std::unique_ptr<syncable_prefs::PrefServiceSyncable> otr_prefs_;
+  std::unique_ptr<sync_preferences::PrefServiceSyncable> prefs_;
+  std::unique_ptr<sync_preferences::PrefServiceSyncable> otr_prefs_;
   ProfileImplIOData::Handle io_data_;
 #if defined(ENABLE_EXTENSIONS)
   scoped_refptr<ExtensionSpecialStoragePolicy>